CVE-2021-37617
Untrusted Search Path in Nextcloud Desktop Client
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. The Nextcloud Desktop Client invokes its uninstaller script when being installed to make sure there are no remnants of previous installations. In versions 3.0.3 through 3.2.4, the Client searches the Uninstall.exe file in a folder that can be written by regular users. This could lead to a case where a malicious user creates a malicious Uninstall.exe, which would be executed with administrative privileges on the Nextcloud Desktop Client installation. This issue is fixed in Nextcloud Desktop Client version 3.3.0. As a workaround, do not allow untrusted users to create content in the C:\ system folder and verify that there is no malicious C:\Uninstall.exe file on the system.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.3
Untrusted Search Path in Nextcloud Desktop Client
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. The Nextcloud Desktop Client invokes its uninstaller script when being installed to make sure there are no remnants of previous installations. In versions 3.0.3 through 3.2.4, the Client searches the Uninstall.exe file in a folder that can be written by regular users. This could lead to a case where a malicious user creates a malicious Uninstall.exe, which would be executed with administrative privileges on the Nextcloud Desktop Client installation. This issue is fixed in Nextcloud Desktop Client version 3.3.0. As a workaround, do not allow untrusted users to create content in the C:\ system folder and verify that there is no malicious C:\Uninstall.exe file on the system.
- Record
CVE-2021-37617- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-426
- Updated
- 2026-11-02
EUVDEUVD-2021-24175
7.3
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. The Nextcloud Desktop Client invokes its uninstaller script when being installed to make sure there are no remnants of previous installations. In versions 3.0.3 through 3.2.4, the Client searches the Uninstall.exe file in a folder that can be written by regular users. This could lead to a case where a malicious user creates a malicious Uninstall.exe, which would be executed with administrative privileges on the Nextcloud Desktop Client installation. This issue is fixed in Nextcloud Desktop Client version 3.3.0. As a workaround, do not allow untrusted users to create content in the C:\ system folder and verify that there is no malicious C:\Uninstall.exe file on the system.
- Record
EUVD-2021-24175- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
NVD
7.3
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. The Nextcloud Desktop Client invokes its uninstaller script when being installed to make sure there are no remnants of previous installations. In versions 3.0.3 through 3.2.4, the Client searches the Uninstall.exe file in a folder that can be written by regular users. This could lead to a case where a malicious user creates a malicious Uninstall.exe, which would be executed with administrative privileges on the Nextcloud Desktop Client installation. This issue is fixed in Nextcloud Desktop Client version 3.3.0. As a workaround, do not allow untrusted users to create content in the C:\ system folder and verify that there is no malicious C:\Uninstall.exe file on the system.
- Record
CVE-2021-37617- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H - CVSS 2.0
- 4.4 Medium
AV:L/AC:M/Au:N/C:P/I:P/A:P - Weakness
- CWE-426, CWE-427
- Updated
- 2026-11-02
OSV
7.3
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. The Nextcloud Desktop Client invokes its uninstaller script when being installed to make sure there are no remnants of previous installations. In versions 3.0.3 through 3.2.4, the Client searches the Uninstall.exe file in a folder that can be written by regular users. This could lead to a case where a malicious user creates a malicious Uninstall.exe, which would be executed with administrative privileges on the Nextcloud Desktop Client installation. This issue is fixed in Nextcloud Desktop Client version 3.3.0. As a workaround, do not allow untrusted users to create content in the C:\ system folder and verify that there is no malicious C:\Uninstall.exe file on the system.
- Record
CVE-2021-37617- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products | EUVD | |
| first indexed | CVE List, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-37617 is a high vulnerability (CVSS 7.3) in Nextcloud Desktop, published August 18, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.46%, the 39th percentile. No source names a fixed version.